Field emission-type electron source and manufacturing method thereof

摘要

A field emission-type electron source (10) is provided with a conductive substrate (1), a semiconductor layer formed on a surface of the conductive substrate (1), at least a part of the semiconductor layer being made porous, and a conductive thin film (7) formed on the semiconductor layer. Electrons injected into the conductive substrate (1) are emitted from the conductive thin film (7) through the semiconductor layer by applying a voltage between the conductive thin film (7) and the conductive substrate (1) in such a manner that the conductive thin film (7) acts as a positive electrode against the conductive substrate (1). The semiconductor layer includes a porous semiconductor layer (6) in which columnar structures (21) and porous structures (25) composed of fine semiconductor crystals of nanometer scale coexist, a surface of each of the structures being covered with an insulating film (22,24). Further, an average dimension of each of the porous structures (25) in a thickness direction of the semiconductor layer is smaller than or equal to 2 mum.